Field of the Invention
The present invention relates to an optical composite layer structure, more particularly to a composite layer structure in combination with a polymer dispersed liquid crystal layer and a touch sensitive transparent conductive layer.
Description of the Related Art
A traditional polymer dispersed liquid crystal (PDLC) is formed by using anisotropic liquid crystal droplets distributing in polymers uniformly, typically anisotropic liquid crystal droplets with positive dielectric constant distributing in polymers uniformly that have no a specific direction in a normal state, and the light transmitted through the anisotropic liquid crystal droplets fails to match with the refractive index of the polymers so that incident light may scatter seriously due to many interfaces existing and light transmission rate is low. If a specific electric field is provided, the anisotropic liquid crystal droplets with positive dielectric constant may be arranged forward along the electric field, and the light transmitted through the anisotropic liquid crystal droplets with positive dielectric constant may match with the refractive index of the polymers so that the most incident light may transmit through forward and the light transmission rate is increased. Smart windows are formed by packaging PDLC in transparent substrates such as conductive glasses and switching the electric field on or off to control the change of transparency of the transparent substrates. Smart windows can dynamically change the tinting of glass to control the amount of light/heat that enters a building. They can also be used to create on-demand private spaces for offices. Recently, soft conductive transparent resins have been used to package PDLC instead of the conductive glasses by the advancing process and material so that the process can be simplified greatly and the application of the related products can be enhanced greatly. For example, the structure of soft conductive transparent resins packaging PDLC in combination with transparent adhesive technologies can be attached on glass of buildings, windows of cars, refrigerators or projection walls for increasing use of applications.
Recently, a laminate structure of PDLC layer in combination with a touch sensitive layer that can produce a change of transparency of PDLC by an electric field block or dot array setting in combination with external wired or wireless switch and touch sensitive operation, as shown in FIG. 1. The structure comprises a polymer dispersed liquid crystal composite layer 100, a first optical adhesive layer 200 and a touch sensitive composite 300. The polymer dispersed liquid crystal composite layer 100 includes an upper transparent substrate 101, a lower transparent substrate 102, an upper transparent conductive layer 103, a lower transparent conductive layer 104 and a PDLC layer 105. The touch sensitive composite 300 is provided on a side surface of the first optical adhesive layer 200, and the touch sensitive composite 300 at least includes a first touch sensitive composite 301, a second touch sensitive composite 302, a second optical adhesive layer 303 and an optical cover layer 304. The structure can produce the change of images and has ease of use. However, the structure is complex that may result in a high material cost, and the optical transparency of the structure is greatly reduced.